What Causes Discomfort In The Chest With Severe Headache And Fainting?

My daughter has been seeing her doctor for tightness in her chest, she passed out, sever headaches she has been sleeping more than normal and alot if water she gas bever been one to drink alot Shes 16 her doctor us at a loss as to what coukd be causing these symptoms she sent her for an eeg and the results were she had abnormalities on her right side of her brain